Clutchless compressor

ABSTRACT

Disclosed is a clutchless compressor which is structured to interrupt power transmission from a vehicle engine to a compressor which is actuated by the engine at occurrence of overload torque. The clutchless compressor comprises: a pulley actuated by an engine; a connector member tightly fixed to an inner periphery of the pulley, and having a number of break portions defined by slots formed along the circumferential direction thereof; and a disk plate mounted on the connector member to be coupled with the connector member while being connected with a rotational shaft of the compressor. The pulley is coupled with the disk plate via the connector member which is tightly fixed to the pulley, and the break portions in the connecting member are broken in order to reduce the number of components necessary for coupling and breaking thereby to save manufacturing cost and facilitate assembly.

TECHNICAL FIELD

The present invention relates to a clutchless compressor, moreparticularly, which is structured to interrupt power transmission from avehicle engine to a compressor which is actuated by the engine atoccurrence of overload torque.

BACKGROUND ART

In general, an air conditioning system of a vehicle serves to maintainthe temperature of a vehicle indoor lower than that of a vehicle outdoorbased upon a circulation cycle of refrigerant such as compression,condensation, expansion and evaporation process. The air conditioningsystem essentially has a compressor, a condenser, an expansion valve andan evaporator which constitute the circulation cycle.

Recently, there is a gradual increase in a demand for variablecompressors that can variably adjust the power according to airconditioning conditions. Such a variable compressor does not need aclutch for regulating driving power which is transmitted from an engineto the compressor.

In the clutchless compressor as above, when a trouble such as seizingoccurs within the compressor, an overload torque exceeding a generallytransmitted torque may take place, stopping rotation of a pulley foractuating the compressor. Then, a belt actuated by the engine continuesto slip on the pulley so that it may be worn and broken by accompaniedresistant heat.

As an approach to solve the above problems, Korean Patent Laid-openPublication No.10-2000-29525 filed by the present assignee discloses aclutchless compressor which is designed to interrupt power transmission.

FIG. 1 is a side sectional view of a conventional clutchless compressor,and FIG. 2 is a perspective view of a pulley and a cover plate shown inFIG. 1.

As shown in FIG. 1, a clutchless compressor comprises a circular pulley100 connected with an engine via a belt 111 and a circular cover plate200 which is installed in proximity of a side of the pulley 100 to beconnected with a power shaft 112 a of a compressor 112. The pulley 100is coupled with the cover plate 200 via a coupling means 300.

As shown in FIG. 2, the coupling means 300 includes break members 301coupled to the pulley 100 and holding members 302 provided in a face ofthe cover plate 200 opposite to the pulley to be coupled with the breakmembers 301. Each of the break members 301 includes an outer body 310made of soft material and having at least one groove 311 in the outerperiphery and an inner body 312 which is wrapped by the outer body 310and has a groove 313 so that the holding member 302 can pass through thegroove 313 for idle rotation when the outer body 310 is fractured by theholding member 302. The each holding member 302 also has a body 320 andprojections 321 extended from both ends of the body 320 to be insertedinto the grooves 311 of the outer body 310.

The holding members 302 are fixed respectively to the break members 301to transmit power from the pulley 100 to the cover plate 200 (refer to amagnified part in FIG. 1). When a torque exceeding a threshold occurs atthe compressor 112, the outer bodies 310 of the break members 301 whichare relatively fragile than the holding members 302 are fractured anddetached from the inner bodies 312 and the projections 321 of theholding members 302 pass through the grooves 313 to interrupt powertransmission to the cover plate 200.

In the conventional clutchless compressor as above, the fractured outerbodies 310 may remain within the cover plate 200 to probably clog thegrooves 313.

Moreover, the conventional coupling means 300 includes a number of partssuch as the break members 301 each having the outer body 310 and theinner body 312, fastening member such as rivets 400 for coupling thebreak members 301 to the pulley 100, the holding members 302 andfastening means such as rivets 400 for coupling the break members 301 tothe cover plate 200 to increase fabrication unit price and assemblycost.

DISCLOSURE OF INVENTION

The present invention has been devised to solve the foregoing problemsand it is therefore an object of the invention to provide a clutchlesscompressor structured to reliably interrupt power transmission in whichthe number of parts is reduced to save manufacturing cost and facilitateassembly.

According to an aspect of the invention, there is provided a clutchlesscompressor comprising: a pulley actuated by an engine; a connectormember tightly fixed to an inner periphery of the pulley, and having anumber of break portions defined by slots formed along thecircumferential direction thereof; and a disk plate mounted on theconnector member to be coupled with the connector member while beingconnected with a rotational shaft of the compressor.

It is preferred that the connector member includes an insert portionclosely fit into the inner periphery of the pulley, and a couplingportion coupled with the disk plate, wherein the break portions connectthe insert portion with the coupling portion.

It is preferred that the coupling portion has a number of projectionsprojected radially from peripheral portions thereof, and the disk platehas coupling recesses formed in a face opposite to the pulley tocorrespond to the number of the projections, whereby the projections areinserted into the coupling recesses to connect the disk plate with theconnector member.

In addition, a number of dampers are interposed between the projectionsand the coupling recesses, the dampers each being formed of a dampingmaterial.

It is preferred that the connector member includes: an insert portionclosely fit into an inner periphery of the pulley; a flange connectedwith the insert portion and seated on a front portion of the pulley; anda coupling portion having a number of connecting slots formed along thecircumferential direction thereof and coupled with the disk plate,wherein the break portions connect the flange with the coupling portion.

It is preferred that the disk plate has connecting projections formed ina face thereof opposite to the pulley to correspond to the number of theconnecting slots, the connecting projections being coupled with theconnecting slots.

In addition, a number of dampers are interposed between the connectingslots and the connecting projections, each of the dampers being formedof a damping material.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side sectional view of a conventional clutchless compressor;

FIG. 2 is a perspective view of a pulley and a cover plate shown in FIG.1;

FIG. 3 is an exploded perspective view of a clutchless compressoraccording to a first embodiment of the invention;

FIG. 4(a) is a perspective view of a connector member of the clutchlesscompressor shown in FIG. 3;

FIG. 4(b) is a side elevation view of a connector member of theclutchless compressor shown in FIG. 3;

FIG. 5 is a side sectional view of the assembled state of the clutchlesscompressor shown in FIG. 3;

FIG. 6 is an exploded perspective view of a clutchless compressoraccording to a second embodiment of the invention;

FIG. 7(a) is a perspective view of a connector member of the clutchlesscompressor shown in FIG. 6;

FIG. 7(b) is a side elevation view of a connector member of theclutchless compressor shown in FIG. 6; and

FIG. 8 is a side sectional view of the assembled state of the clutchlesscompressor shown in FIG. 6.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention will be described in detailhereinafter with reference with the appended drawings.

FIG. 3 is an exploded perspective view of a clutchless compressoraccording to an embodiment of the invention, FIG. 4(a) is a perspectiveview of a connector member of the clutchless compressor shown in FIG. 3,FIG. 4(b) is a side elevation view of a connector member of theclutchless compressor shown in FIG. 3, and FIG. 5 is a side sectionalview of the assembled state of the clutchless compressor shown in FIG.3.

As shown in FIG. 3, the clutchless compressor of the first embodimentcomprises a pulley 10 actuated by an engine, a connector member 30 whichis tightly fixed to the inner periphery of the pulley 10 and has breakportions 33 defined by slots formed along the circumferential directionthereof; and a disk plate 20 mounted on the connector member 30 to becoupled with the connector member 30 while being connected with arotational shaft of the compressor.

The pulley 10 is made of metal or plastic, with a through hole formed inits central portion. The connector member 30 is closely fixed to theinner periphery of the through hole. On the outer periphery of thepulley 10, there is placed a belt (not shown) which is actuated by theengine.

The connector member 30 which is arranged in the inner periphery of thepulley 10 as described above is preferably made of metal such asaluminum or plastic. As shown in FIGS. 4(a) and 4(b), in a lower portionof the connector member 30, there is provided an insert portion 31 whichis tightly fit into the inner periphery of the pulley 10. Above theinsert portion 31, there is provided a coupling portion 32 of a diametersmaller than that of the insert portion 31.

Further, the break portions 33 are formed between the insert portion 31and the coupling portion 32 to connect the insert portion 31 with thecoupling portion 32. The break portions 33 are designed to be brokenwhen a torque exceeding a threshold is applied to the break portions 33.A bearing 50 is fixedly installed in the inner periphery of the insertportion 31.

Further, a number of projections 34 projected radially from the outerperiphery of the coupling portion 32 are wrapped in dampers 40 whichwill be described later.

The disk plate 20 is preferably made of plastic, and has a hub 22installed in a central portion of the disk plate 20 and connected with arotational shaft of the compressor. The hub 22 preferably is made ofmetal such as steel. It is preferred that the disk plate 20 isintegrally formed with the hub 22 by integrally injecting plastic to thehub 22.

The disk plate 20 has coupling recesses 21 which are formed in a faceopposite to the pulley 10 to correspond to the number of the projections34 and in which the dampers 40 are installed. The coupling recesses 21have insert grooves 23 at both sides for receiving fixing portions 41 ofthe dampers 40.

It is preferred that each of the dampers 40 is made of buffer materialsuch as rubber, and shaped as a ring, as shown in FIG. 3, which isperforated downward. The inner periphery of the damper 40 is formed tomatch each of the projections 34 so that the projection 34 can beinserted into the damper 40. The outer periphery of the damper 40 isformed to match each of the coupling recesses 21 so that the damper 40can be inserted into the coupling recess 21. On the outer periphery ofthe damper 40, there are formed fixing portions 41 which are insertedinto the insert grooves 23. The dampers 40 of the above type function torelieve impact and alleviate vibration during operation of thecompressor.

While it has illustrated in this embodiment that six projections 34 andthree break portions 33 are formed, the number of the projections 34 isnot limited to 6 or the number of the break portions 33 is not alsolimited to 3. The projections 34 and the break portion 33 may be formedof different numbers.

Hereinafter an assembly process of the variable compressor of thisembodiment will be described with reference to FIGS. 3 and 5. Thebearing 50 is first fixed to the inner periphery of the insert portion31 of the connecting member 30. The insert portion 31 is tightly fixedto the inner periphery of the pulley 10 through press fit or doubleinjection. Then, each of the dampers 40 is inserted into a correspondingprojection 34 of the coupling portion 32, and into a correspondingcoupling recess 21 of the disk plate 20 which is formed integral withthe hub 22 (Refer to FIG. 3). Then, the rotational shaft (not shown) ofthe compressor is coupled with the hub 22 to complete the assemblyprocess.

Hereinafter the operation of the clutchless compressor of thisembodiment will be described.

When the pulley 10 is actuated by a belt (not shown) connected with anengine (not shown), a rotational torque is transmitted to the disk plate20 via the connector member 30 to drive a compressor rotational shaft(not shown) connected with the hub 22.

If an obstacle such as seizing occurs within the compressor to stoprotation of the shaft, a torque larger than the rotational torque isapplied to the disk plate 20. If the torque value exceeds a threshold,the break portion 33 of the connector member 30 is broken.

As a result, the disk plate 20 connected with the compressor rotationalshaft stops its rotation, but the pulley 10 tightly fixed with theinsert portion 31 of the connector member 30 continuously rotates, so asto prevent a potential accident that the belt is slipped off the outerperiphery of the pulley to damage itself.

Hereinafter the second embodiment of the invention will be described indetail.

FIG. 6 is an exploded perspective view of a clutchless compressoraccording to the second embodiment of the invention, FIG. 7(a) is aperspective view of a connector member of the clutchless compressorshown in FIG. 6, FIG. 7(b) is a side elevation view of a connectormember of the clutchless compressor shown in FIG. 6, and FIG. 8 is aside sectional view of the assembled state of the clutchless compressorshown in FIG. 6.

As shown in FIG. 6, the clutchless compressor of this embodimentcomprises a pulley 10 actuated by an engine, a connector member 70 whichis tightly fixed to the inner periphery of the pulley 10 and has breakportions 74 defined by peripheral slots; and a disk plate 60 coupledwith the connector member 70 and connected with a rotational shaft ofthe compressor.

This embodiment is the same as the first embodiment except for the diskplate 60 and the connector member 70, in which detailed description ofthe same construction will be omitted.

The connector member 70 is preferably made of metal such as aluminum orplastic. As shown in FIGS. 6, 7(a) and 7(b), the connector member 70 hasan insert portion 71 in a lower portion thereof to be tightly fit intothe inner periphery of the pulley 10, a flange 72 connected with theinsert portion 71 to be seated on a front face of the pulley 10 and acoupling portion 73 formed above the flange 72 to be connected with thedisk plate 60.

The insert portion 71 will not be described in detail since it issubstantially the same as that in the first embodiment, in which abearing 50 is fixed to the inner periphery of the insert portion 71.

The flange 72 has a diameter larger than a through hole of the pulley 10as shown in FIGS. 6 and 8 in order to support the connector member 70 infront of the pulley 10.

In a face of the coupling portion 73 opposed to the disk plate 60, thereare provided a number of connecting slots 75 along the circumferentialdirection of the coupling portion 73 for receiving connector projections61 of the disk plate 60 which will be described later.

Further, a number of break portions 74 are provided between the flange72 and the coupling portion 73 to connect the flange 72 with thecoupling portion 73. The break portions 74 are designed to be broken ata torque exceeding a threshold.

In a face of the disk plate 60 opposed to the pulley 10, connectingprojections 61 are projected to be inserted into the connecting slots75, formed of the number the same as that of the connecting slots 75.Preferably, dampers 80 made of buffer material such as rubber areinterposed between the connecting slots 75 and the connectingprojections 61 to provide a buffering function.

On the other hand, a number of connecting slots 75 can be formed in aface of the disk plate 60 and the connecting projections 61 can beformed in a face of the coupling portion 73. The number of connectingslots 75 is the same as that of connecting projections 61.

While it has illustrated in this embodiment that six projections 34 andthree break portions 33 are formed, the number of the projections 34 isnot limited to 6 or the number of the break portions 33 is not alsolimited to 3.

Hereinafter an assembly process of this embodiment will be describedwith reference to FIGS. 6 and 8. The bearing 50 is fixed to the innerperiphery of the insert portion 71 of the connector member 70, and theinsert portion 71 is tightly fixed to the inner periphery of the pulley10 via press fit or double injection. Then, the connecting projections61 of the disk plate 60 are inserted into the connecting slots 75 of thecoupling portion 73. Preferably, the dampers 80 are interposed betweenthe connecting slots 75 and the connecting projections 61 as describedabove. A rotational shaft (not shown) of the compressor is coupled withthe hub 22 to complete the assembly process.

The operation of the clutchless compressor of this embodiment will notbe described since it is substantially the same as the afore-describedone of the first embodiment.

In this embodiment, the connector member 70 may have only threecomponents of the flange 72, the coupling portion 73 and the breakportions 74 without the insert portion 71 to be fixedly inserted into afront face of the pulley 10.

INDUSTRIAL APPLICABILITY

According to the clutchless compressor of the invention, the pulley iscoupled with the disk plate via the connector member which is tightlyfixed to the pulley, and the break portions in the connector member arebroken in order to reduce the number of components necessary forcoupling and breaking thereby to save manufacturing cost and facilitateassembly.

Further, the break portions are attached to the insert portion and thecoupling portion of the connector member even after being broken inorder not to obstruct rotation of the pulley so that power transmissioncan be reliably interrupted.

1. A clutchless compressor comprising: a pulley actuated by an engine; aconnector member fixed to an inner periphery of the pulley and having anumber of break portions formed along the circumferential directionthereof; and a disk plate mounted on the connector member to be coupledwith the connector member while being connected with a rotational shaftof the compressor.
 2. The clutchless compressor according to claim 1,wherein the connector member includes: an insert portion fit into theinner periphery of the pulley and a coupling portion coupled with thedisk plate and wherein the break portions connect the insert portionwith the coupling portion.
 3. The clutchless compressor according toclaim 1, wherein the coupling portion has a number of projectionsprojected radially from peripheral portions thereof, and the disk platehas coupling recesses formed in a face opposite to the pulley tocorrespond the projections, whereby the projections are inserted intothe coupling recesses to connect the disk plate with the connectormember.
 4. The clutchless compressor according to claim 3, wherein anumber of dampers are interposed between the projections and thecoupling recesses.
 5. The clutchless compressor according to claim 1,wherein the connector member includes: an insert portion fit into aninner periphery of the pulley; a flange connected with the insertportion and seated on a front portion of the pulley; and a couplingportion coupled with the disk plate, and wherein the break portionsconnect the flange with the coupling portion.
 6. The clutchlesscompressor according to claim 5, wherein a number of connecting slotsare formed along the circumferential direction on a face of a couplingportion opposite to the disk plate, and wherein the disk plate hasconnecting projections formed in a face thereof opposite to the pulleyto correspond to the connecting slots.
 7. The clutchless compressoraccording to claim 6, wherein a number of dampers are interposed betweenthe connecting slots and the connecting projections.